Abstract

Respiratory allergy, which consists of allergic rhinitis (AR) and allergic asthma (AA), requires high cost of medical treatment. These medications can only temporally relieve the allergic symptoms without any modification of an allergic hypersensitivity status. The only option that can modify the immunologic status is the allergen immunotherapy Three hundred and forty three subjects with chronic rhinitis was screened from 13 centers in Thailand. One hundred and forty six patients had been recruited according to the inclusion criteria, in which 108 subjects was randomly assigned into the intervention group (receiving immunotherapy and standard treatment) and 36 subjects had been assigned to the controlled group (receiving standard treatment with placebo injection). The clinical characteristics between two groups were not statistically significant. After one year, the median composite score in the intervention group decreases 3.8 score comparing to the baseline (p < 0.001). But comparison between the intervention group and control group was not statistically significant. After one year of treatment, 66.7 percent of subjects in the intervention group can reduce their medication use by 50%. Moreover, 23% of subjects in the intervention group were medication-free after 1 year of allergen immunotherapy. Eighty five percent of subject tolerate the 500 allergen unit dosage of vaccine. There were 423 adverse events (AE) out of 4,444 injections, 2.31% of total AEs (77/423 events) were systemic reactions.